The present invention relates to a check valve assembly and, more particularly, to a check valve assembly which may be quickly assembled and disassembled for replacement of a regulator portion of the check valve.
The check valve of the present invention is directed toward applications in pipe lines in which low back pressures are experienced. Specifically, swimming pools, spas and tanks have plumbing structures which often require check valves to prevent back flow from filtration systems located at a higher elevation than the motor and pump used to force fluid through the system. Similar check valves may also be used on manifold piping systems where two or more pumps may operate independently of each other and/or at different time intervals. Such check valves may also be used directly in conjunction with pumps wherein the check valve maintains fluid in the housing for priming purposes.
Typically, check valves for swimming pools and spas are installed on the suction side of the pump to control unidirectional flow of water and chemicals to the pump from the pool or spa, and to prevent back flow of the fluid from the pump which may result in debris being deposited in the pool or spa.
Prior check valves have been constructed of various materials including iron, brass, steel, PVC, ABS, polyethylene and polypropylene. Such valves have also included varied configurations including a swinging gate type valve incorporating an elastomeric seal, a plunger cooperating with a seal and biased to a desired position by compression spring and configurations incorporating a movable ball which moves into and out of sealing contact with an orifice.
A common problem with prior valves is that it has been difficult to provide a good back flow seal while also providing for minimum restriction t forward flow through the valve. In addition, many prior art valves have required a large amount of installation space to accommodate the regulator structure operating to control the flow through the valve. Further, most existing valves cannot be repaired and must be cut out of the piping system and replaced with a new valve when the seals on the valve fail or other problems occur in the operation of the valve.
Accordingly, there is a need for a check valve which may be installed into a pool or spa fluid piping system to control unidirectional flow of fluid through the system. The valve should have a compact construction and be easily repaired without the need for cutting or moving the pipe to accommodate the repair operation.
Further, there is a need for a valve which will provide an effective seal against back flow without significantly inhibiting forward flow characteristics of the piping system such that the valve causes a minimal pressure drop within the system.